1. Field of the Invention
This invention relates to an apparatus such as a camera or the like adapted to use a film cartridge and more particularly to a device for loading or unloading the film cartridge on or from the apparatus.
2. Description of the Related Art
Generally a film cartridge adapted for cameras have some play between a spool disposed within the film cartridge and the shell of the film cartridge. It has been, therefore, hardly possible to keep a film cartridge accurately in position on a camera due to the vertical rattling of a spool and the tilting of its axis taking place within the cartridge while the film is in process of transportation, although the cartridge shell is set in position when the film cartridge is loaded on the camera.
Meanwhile film cartridges of varied kinds have recently been proposed. One example of them, disclosed in Japanese Laid-Open Patent Application No. HEI 3-75637, is arranged as shown in FIG. 17. As shown, when a film 52 contained in a cartridge 50 is in an initial state and has not been exposed, its leader part remains also within the cartridge 50 in a state of being blocked from light.
In using this cartridge 50 for a camera, a spool 51 which is disposed within the cartridge 50 is rotated by a film transport mechanism of the camera to move the film 52 out of the cartridge 50 by thrust driving. In this instance, the film must be accurately sent out and moved in between an aperture and a pressing plate of the camera without slanting the film too much.
Further, a camera system disclosed, for example, in U.S. Pat. No. 4,864,332 is arranged not only to expose a film to light to optically take a shot of a scene but also to have a magnetic recording area in a part of the film surface and to magnetically record or read out information of varied kinds on or from the recording area while the film is in process of transportation. However, in the case of the camera of this kind, it is necessary for accurate magnetic recording or reading to have the film come to a magnetic head at a stable entrance angle in sending the film out of a film cartridge. In cases where information of varied kinds is to be optically recorded in the form of dots or lines, instead of magnetic recording, the film also must be stably sent out from the cartridge.
This requirement can be hardly met by the conventional arrangement of carrying the spool of a film cartridge only at one end of it (with a fork arranged to engage one end of it), like the conventional 35 mm film containing cartridge. The conventional arrangement hardly ensures an adequate entrance angle at which the film comes in between the aperture and the pressing or pushing plate and hardly prevents the film from vertically rattling while the film is in process of transportation. In order to accurately keep the cartridge in position within the camera, the end of the spool must be carried with a severer degree of dimensional precision.
In the case of the camera 54 as shown in FIG. 18 the lid 53 of a cartridge chamber 55 is arranged to be opened and closed by sliding it approximately in parallel to the driving plane of the spool 51. Practice has been to provide the cartridge chamber lid 53 with a plastic protection arranged to hold the other end of the cartridge 50. However, the projection hinders the sliding motion of the cartridge chamber lid 53. Besides, with differences in dimension among individual cartridges, an error in inserting the cartridge 50, the play provided for sliding the cartridge chamber lid 53, a dimensional error existing within the cartridge chamber 55, etc. taken into consideration, they add up to a large tolerance requiring a considerably large space, even if the dimensions relative to the cartridge chamber lid 53 are minimized within the range of tolerance. Therefore, the play or rattling of the cartridge which takes place within the camera can be hardly reduced by such arrangement.